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Contra Wirecutter on the IKEA air purifier

dynomight.net

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Re: Contra Wirecutter on the IKEA air purifier

#351

Post by nojs »

hypersoar wrote: post #51

The Wirecutter is a highly flawed review site, but at least it's a real one. There are vanishingly few left for general consumer products. There's WC, Consumer Reports, and what else? They've seem to have all been killed off. When I'm researching some category of product, I feel lucky if I find any professional reviews written by people who have actually touched the thing they're reviewing. I know we've all had the e…

Depends how you define “real”. It’s a standard issue affiliate marketing site that recommends products according to deals they have with manufacturers: https://www.xdesk.com/wirecutter-standing-desk-review-pay-to...

Re: Contra Wirecutter on the IKEA air purifier

#352

Post by infinityio »

etchalon wrote: post #302
csours wrote: post #293

Earlier quoted context omitted.

The author explicitly states that it's small in the home use context. If you're talking about medical or cleanroom manufacturing contexts, yes it's a huge difference.

Small home or not, homes are not sealed environments. A 10x difference is a 10x difference. Using one small number or produce another small number, so the difference looks small, doesn't hide the 10x change.

Is it a 10x difference? If you used the better filter, you would still have 99.95% of the particles you would have had if you used the worse filter

Re: Contra Wirecutter on the IKEA air purifier

#353

Post by screye »

wpietri wrote: post #282

Who is Dynomight? For me this piece leans pretty heavily on authorial confidence. But I couldn't find any indication of who the author is, or what his expertise is. I get why he's casting aspersions on their revenue model and how it might affect what they write. But then he doesn't disclose what his revenue model and personal interests might be.

As a reader, if I had to generalize; Dynomight is a SF-rationalist-substack-adjacent blogger with a good understanding of statistics. The 2 closest popular bloggers I associate him with are SSC and Gwern; both pretty popular on HN.

I particularly loved his blogs on the homelessness[1] and drug[2] crisis in the US. He? digs deep, does the statistical due diligence and usually finds conclusions that richer-academics-media houses have yet to find. I have found his arguments to be in good faith and are generally unencumbered by the political repercussions of said findings.

[1] https://dynomight.net/homeless-crisis/

[2] https://dynomight.net/p2p-meth/

my 2 cents. Don't actually know him or anything.

Re: Contra Wirecutter on the IKEA air purifier

#354

Post by armadsen »

fnimick wrote: post #334
fartcannon wrote: post #329

Earlier quoted context omitted.

Do you trust Linus, though? He often promotes himself as without bias, but he very clearly hates Apple (except the watch). He also loves things he already understands (anything Microsoft). He's got heavy duty fanboyitis. And he's clearly someone you can buy demonstrated by his flip flopping AMD/Intel/NVidia praise. I don't think he outwardly lies (at least not in a way that matters), or anything, but he's got pretty…

He's also vocally anti-union and actively tried to stop his employees from marketing themselves on personal social media (to stop them from building a following and then leaving, I'm guessing), so I refuse to watch any of his content or support his business in any way now.

I know this is completely subjective, and his millions of subscribers tell me my opinion is far from ubiquitous, but he's also just straight up obnoxious to me. One of those people whose voice, demeanor, appearance, everything, just immediately turns me off.

Re: Contra Wirecutter on the IKEA air purifier

#355

Post by tuna-piano »

hypersoar wrote: post #51

The Wirecutter is a highly flawed review site, but at least it's a real one. There are vanishingly few left for general consumer products. There's WC, Consumer Reports, and what else? They've seem to have all been killed off. When I'm researching some category of product, I feel lucky if I find any professional reviews written by people who have actually touched the thing they're reviewing. I know we've all had the e…

rtings.com has great reviews for electronics, measuring detailed metrics and putting them through various tests. (for example, their AirPods Pro review: https://www.rtings.com/headphones/reviews/apple/airpods-pro-...)

Outdoor Gear Lab for outdoor product reviews: https://www.outdoorgearlab.com/topics/camping-and-hiking/bes...

Re: Contra Wirecutter on the IKEA air purifier

#356

Post by rcoveson »

csours wrote: post #340
rcoveson wrote: post #322

Earlier quoted context omitted.

The difference between 0.9005 and 0.90005 is not huge in a medical context, or in a chip fab context, or in any other practical context. We're not talking about the difference between 0.0005 and 0.00005. The numbers in question are 0.9005 and 0.90005, and the point being made is that the 0.9 problem dwarfs the 10x efficiency difference way over in the thousandths place.

That difference is from his comments on the toy model of 1000 cubic feet room and 100 cubic feet per minute recirculating air. In an operating room or chip fab, the room would be over pressure and the new air coming into the room would be filtered. The cleanliness of that air would be determined by the quality of the filter. Also, if you need air that clean, you need to have strategies for all sorts of things besides…

Yes, the numbers are from a toy example, one that the author used to make one uncontroversial point in one section of the post. Those are the numbers we are discussing in this subthread, which began with:

> The idea that the difference between 0.9005 and 0.90005 is "small" is … weird.

We aren't talking about a situation where both filters are processing all the air in the room. We're talking about a situation where the filters are only processing 10% of the air in the room. That's the defining characteristic of the hypothetical.

Re: Contra Wirecutter on the IKEA air purifier

#357

Post by jefftk »

csours wrote: post #340
rcoveson wrote: post #322

Earlier quoted context omitted.

The difference between 0.9005 and 0.90005 is not huge in a medical context, or in a chip fab context, or in any other practical context. We're not talking about the difference between 0.0005 and 0.00005. The numbers in question are 0.9005 and 0.90005, and the point being made is that the 0.9 problem dwarfs the 10x efficiency difference way over in the thousandths place.

That difference is from his comments on the toy model of 1000 cubic feet room and 100 cubic feet per minute recirculating air. In an operating room or chip fab, the room would be over pressure and the new air coming into the room would be filtered. The cleanliness of that air would be determined by the quality of the filter. Also, if you need air that clean, you need to have strategies for all sorts of things besides…

> In an operating room or chip fab, the room would be over pressure and the new air coming into the room would be filtered.

You're describing a situation where the filter is on the intake, but this thread and article are about purifiers within rooms. I agree that the math is really different in your situation.

Re: Contra Wirecutter on the IKEA air purifier

#358

Post by jonahhorowitz »

hypersoar wrote: post #51

The Wirecutter is a highly flawed review site, but at least it's a real one. There are vanishingly few left for general consumer products. There's WC, Consumer Reports, and what else? They've seem to have all been killed off. When I'm researching some category of product, I feel lucky if I find any professional reviews written by people who have actually touched the thing they're reviewing. I know we've all had the e…

Since some are throwing out good, more specific, gear tests. I'd like to throw out Baby Gear Lab (https://www.babygearlab.com) if you need baby stuff. They're way better than the Wirecutter because they're run by experts in baby gear. (I'm not affiliated in any way, but I'm a new parent that found it super useful.)

Re: Contra Wirecutter on the IKEA air purifier

#359

Post by tempestn »

csours wrote: post #340
rcoveson wrote: post #322

Earlier quoted context omitted.

The difference between 0.9005 and 0.90005 is not huge in a medical context, or in a chip fab context, or in any other practical context. We're not talking about the difference between 0.0005 and 0.00005. The numbers in question are 0.9005 and 0.90005, and the point being made is that the 0.9 problem dwarfs the 10x efficiency difference way over in the thousandths place.

That difference is from his comments on the toy model of 1000 cubic feet room and 100 cubic feet per minute recirculating air. In an operating room or chip fab, the room would be over pressure and the new air coming into the room would be filtered. The cleanliness of that air would be determined by the quality of the filter. Also, if you need air that clean, you need to have strategies for all sorts of things besides…

Yes, but in that case you wouldn't be comparing 0.9005 and 0.90005, but rather 0.0005 and 0.00005. No one is arguing that the difference in filters wouldn't matter in a cleanroom context, just that recirculating air in a home the difference in filtration is more like 0.9005 vs 0.90005, and the difference between those numbers is small (in any context to which they apply).

Re: Contra Wirecutter on the IKEA air purifier

#360

Post by rootlocus »

etchalon wrote: post #344
rootlocus wrote: post #328

Earlier quoted context omitted.

Consider a purifier that purifies 99.995%. According to your "probabilities", that's a 100x improvement. Now consider this purifier purifies 1 cubic millimeter of air per hour. That is to say, each hour 1 cubic millimeter of air is 99.995% purified (no probability). Would you say that this purifier is 100x better than the IKEA one with 99.5% purification at 1 cubic feet of air per minute? Considering air flow is not…

A E12 filter filters out 99.5% of particles above 0.3 microns. An H13 filter filters out 99.95% of particles above 0.3 microns. Assuming a volume of 10000 particles above 0.3 microns: An E12 filter will leave 50 particles. An H13 filter will leave 5 particles. The "rootlocus" filter would leave 0.5 particles. So yes, I would say your filter is 100x better because it literally is.

> Assuming a volume of 10000 particles above 0.3 microns:

That volume is not the same volume processed by all filters in the same amount of time.

In the first minute:

    E12  filters 10000 particles   @ 99.5% performance   -> removes 9950,   leaves 50
    H13  filters 10000 particles   @ 99.95% performance  -> removes 9995,   leaves 5
    RLv1 filters 10 particles      @ 99.995% performance -> removes 10,     leaves 0
    RLv2 filters 1000000 particles @ 99% performance     -> removes 990000, leaves 10000
RLv1 only filters a tiny amount of air each minute, while RLv2 filters a lot of air each minute (I've improved the flow, but drastically botched the performance)

By your method, RLv2 is 2000x slower than H13, but in the same ammount of time filtered 99x more particles. RLv1 needs to run 99000 minutes to filter the same amount of particles RLv2 does in one minute.

The example is meant to show air flow totaly dominates performance, and it's not "a trick" to multiply by it. I also want to point out that comparing the amount of particles "left" (50 vs 5 vs 0 vs 10000) is nonsense and absolutely no indication of performance in any way.

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